1. Technical Field
The present disclosure relates to an imaging device comprising a fixed focused lens and an image sensor comprising a plurality of pixels arranged on a semiconductor substrate and supplying image data and electronic means for reading the image matrix.
2. Description of the Related Art
Imaging devices typically comprise a lens and an image sensor in the form of a semiconductor chip comprising a matrix of pixels. These devices may be used for a wide range of applications including “machine vision” such as visual inspection of merchandise or facial recognition wherein an image is captured and processed. The device may further include an ambient light sensor (“ALS”) functionality, for example to process a captured image depending on the amount of ambient light present, or to adjust a display intensity on a television monitor. Currently, such devices are being integrated into many devices including mobile telephones, personal digital assistants (PDAs), personal computers, music players, televisions, automobiles, etc.
It is known to use the matrix of pixels to perform both ambient light sensing and image capture functions. To sense the ambient light, the lens is unfocused so that the pixels may receive ambient light from as wide a view as possible. The lens is then re-focused for the image capture. Ambient light sensing and image capture are therefore done sequentially. Such a process is slow and not applicable when the lens cannot be focused and unfocused, which concerns many low-cost imaging devices.